The present disclosure herein relates to a lens technique, and more particularly, to a varifocal lens technique.
Optical lenses are formed of a rigid material, such as glass or plastic, which is not easily deformed. In this case, when a subject is to be viewed through a lens, it is inconvenient to move the lens in the optical axis direction to focus the subject. Due to this limitation, most cameras requisitely have cylindrical lens barrels, and should use a method of rotating a motor inside the lens to automatically move the lens.